Merging upstream version 1.72.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

7 files changed, 205 insertions, 92 deletions

diff --git a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
index f41795d60..cfcf31fce 100644
--- a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
@@ -180,24 +180,25 @@ trait TypeOpInfo<'tcx> {
             return;
         };
 
-        let placeholder_region = tcx.mk_re_placeholder(ty::Placeholder {
-            universe: adjusted_universe.into(),
-            bound: placeholder.bound,
-        });
-
-        let error_region =
-            if let RegionElement::PlaceholderRegion(error_placeholder) = error_element {
-                let adjusted_universe =
-                    error_placeholder.universe.as_u32().checked_sub(base_universe.as_u32());
-                adjusted_universe.map(|adjusted| {
-                    tcx.mk_re_placeholder(ty::Placeholder {
-                        universe: adjusted.into(),
-                        bound: error_placeholder.bound,
-                    })
-                })
-            } else {
-                None
-            };
+        let placeholder_region = ty::Region::new_placeholder(
+            tcx,
+            ty::Placeholder { universe: adjusted_universe.into(), bound: placeholder.bound },
+        );
+
+        let error_region = if let RegionElement::PlaceholderRegion(error_placeholder) =
+            error_element
+        {
+            let adjusted_universe =
+                error_placeholder.universe.as_u32().checked_sub(base_universe.as_u32());
+            adjusted_universe.map(|adjusted| {
+                ty::Region::new_placeholder(
+                    tcx,
+                    ty::Placeholder { universe: adjusted.into(), bound: error_placeholder.bound },
+                )
+            })
+        } else {
+            None
+        };
 
         debug!(?placeholder_region);
 
@@ -390,7 +391,7 @@ fn try_extract_error_from_fulfill_cx<'tcx>(
         error_region,
         &region_constraints,
         |vid| ocx.infcx.region_var_origin(vid),
-        |vid| ocx.infcx.universe_of_region(ocx.infcx.tcx.mk_re_var(vid)),
+        |vid| ocx.infcx.universe_of_region(ty::Region::new_var(ocx.infcx.tcx, vid)),
     )
 }
 
@@ -411,7 +412,7 @@ fn try_extract_error_from_region_constraints<'tcx>(
                 }
                 // FIXME: Should this check the universe of the var?
                 Constraint::VarSubReg(vid, sup) if sup == placeholder_region => {
-                    Some((infcx.tcx.mk_re_var(vid), cause.clone()))
+                    Some((ty::Region::new_var(infcx.tcx, vid), cause.clone()))
                 }
                 _ => None,
             }
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 15d73ed73..c8c8b72b3 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -1,6 +1,5 @@
-use std::iter;
-
 use either::Either;
+use hir::PatField;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_errors::{
@@ -14,9 +13,10 @@ use rustc_infer::traits::ObligationCause;
 use rustc_middle::hir::nested_filter::OnlyBodies;
 use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::{
-    self, AggregateKind, BindingForm, BorrowKind, ClearCrossCrate, ConstraintCategory,
-    FakeReadCause, LocalDecl, LocalInfo, LocalKind, Location, Operand, Place, PlaceRef,
-    ProjectionElem, Rvalue, Statement, StatementKind, Terminator, TerminatorKind, VarBindingForm,
+    self, AggregateKind, BindingForm, BorrowKind, CallSource, ClearCrossCrate, ConstraintCategory,
+    FakeReadCause, LocalDecl, LocalInfo, LocalKind, Location, MutBorrowKind, Operand, Place,
+    PlaceRef, ProjectionElem, Rvalue, Statement, StatementKind, Terminator, TerminatorKind,
+    VarBindingForm,
 };
 use rustc_middle::ty::{self, suggest_constraining_type_params, PredicateKind, Ty};
 use rustc_middle::util::CallKind;
@@ -27,6 +27,7 @@ use rustc_span::symbol::{kw, sym, Ident};
 use rustc_span::{BytePos, Span, Symbol};
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::ObligationCtxt;
+use std::iter;
 
 use crate::borrow_set::TwoPhaseActivation;
 use crate::borrowck_errors;
@@ -677,8 +678,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let tcx = self.infcx.tcx;
 
         // Find out if the predicates show that the type is a Fn or FnMut
-        let find_fn_kind_from_did = |(pred, _): (ty::Predicate<'tcx>, _)| {
-            if let ty::PredicateKind::Clause(ty::Clause::Trait(pred)) = pred.kind().skip_binder()
+        let find_fn_kind_from_did = |(pred, _): (ty::Clause<'tcx>, _)| {
+            if let ty::ClauseKind::Trait(pred) = pred.kind().skip_binder()
                 && pred.self_ty() == ty
             {
                 if Some(pred.def_id()) == tcx.lang_items().fn_trait() {
@@ -704,7 +705,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) => tcx
                 .explicit_item_bounds(def_id)
                 .subst_iter_copied(tcx, substs)
-                .find_map(find_fn_kind_from_did),
+                .find_map(|(clause, span)| find_fn_kind_from_did((clause, span))),
             ty::Closure(_, substs) => match substs.as_closure().kind() {
                 ty::ClosureKind::Fn => Some(hir::Mutability::Not),
                 ty::ClosureKind::FnMut => Some(hir::Mutability::Mut),
@@ -775,7 +776,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let predicates: Result<Vec<_>, _> = errors
             .into_iter()
             .map(|err| match err.obligation.predicate.kind().skip_binder() {
-                PredicateKind::Clause(ty::Clause::Trait(predicate)) => {
+                PredicateKind::Clause(ty::ClauseKind::Trait(predicate)) => {
                     match predicate.self_ty().kind() {
                         ty::Param(param_ty) => Ok((
                             generics.type_param(param_ty, tcx),
@@ -926,7 +927,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         // FIXME: supply non-"" `opt_via` when appropriate
         let first_borrow_desc;
         let mut err = match (gen_borrow_kind, issued_borrow.kind) {
-            (BorrowKind::Shared, BorrowKind::Mut { .. }) => {
+            (
+                BorrowKind::Shared,
+                BorrowKind::Mut { kind: MutBorrowKind::Default | MutBorrowKind::TwoPhaseBorrow },
+            ) => {
                 first_borrow_desc = "mutable ";
                 self.cannot_reborrow_already_borrowed(
                     span,
@@ -940,7 +944,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     None,
                 )
             }
-            (BorrowKind::Mut { .. }, BorrowKind::Shared) => {
+            (
+                BorrowKind::Mut { kind: MutBorrowKind::Default | MutBorrowKind::TwoPhaseBorrow },
+                BorrowKind::Shared,
+            ) => {
                 first_borrow_desc = "immutable ";
                 let mut err = self.cannot_reborrow_already_borrowed(
                     span,
@@ -962,7 +969,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 err
             }
 
-            (BorrowKind::Mut { .. }, BorrowKind::Mut { .. }) => {
+            (
+                BorrowKind::Mut { kind: MutBorrowKind::Default | MutBorrowKind::TwoPhaseBorrow },
+                BorrowKind::Mut { kind: MutBorrowKind::Default | MutBorrowKind::TwoPhaseBorrow },
+            ) => {
                 first_borrow_desc = "first ";
                 let mut err = self.cannot_mutably_borrow_multiply(
                     span,
@@ -972,7 +982,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     &msg_borrow,
                     None,
                 );
-                self.suggest_split_at_mut_if_applicable(
+                self.suggest_slice_method_if_applicable(
                     &mut err,
                     place,
                     issued_borrow.borrowed_place,
@@ -982,15 +992,23 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     issued_borrow.borrowed_place,
                     &issued_spans,
                 );
+                self.explain_iterator_advancement_in_for_loop_if_applicable(
+                    &mut err,
+                    span,
+                    &issued_spans,
+                );
                 err
             }
 
-            (BorrowKind::Unique, BorrowKind::Unique) => {
+            (
+                BorrowKind::Mut { kind: MutBorrowKind::ClosureCapture },
+                BorrowKind::Mut { kind: MutBorrowKind::ClosureCapture },
+            ) => {
                 first_borrow_desc = "first ";
                 self.cannot_uniquely_borrow_by_two_closures(span, &desc_place, issued_span, None)
             }
 
-            (BorrowKind::Mut { .. } | BorrowKind::Unique, BorrowKind::Shallow) => {
+            (BorrowKind::Mut { .. }, BorrowKind::Shallow) => {
                 if let Some(immutable_section_description) =
                     self.classify_immutable_section(issued_borrow.assigned_place)
                 {
@@ -1004,7 +1022,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     borrow_spans.var_subdiag(
                         None,
                         &mut err,
-                        Some(BorrowKind::Unique),
+                        Some(BorrowKind::Mut { kind: MutBorrowKind::ClosureCapture }),
                         |kind, var_span| {
                             use crate::session_diagnostics::CaptureVarCause::*;
                             match kind {
@@ -1038,7 +1056,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 }
             }
 
-            (BorrowKind::Unique, _) => {
+            (BorrowKind::Mut { kind: MutBorrowKind::ClosureCapture }, _) => {
                 first_borrow_desc = "first ";
                 self.cannot_uniquely_borrow_by_one_closure(
                     span,
@@ -1052,7 +1070,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 )
             }
 
-            (BorrowKind::Shared, BorrowKind::Unique) => {
+            (BorrowKind::Shared, BorrowKind::Mut { kind: MutBorrowKind::ClosureCapture }) => {
                 first_borrow_desc = "first ";
                 self.cannot_reborrow_already_uniquely_borrowed(
                     span,
@@ -1067,7 +1085,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 )
             }
 
-            (BorrowKind::Mut { .. }, BorrowKind::Unique) => {
+            (BorrowKind::Mut { .. }, BorrowKind::Mut { kind: MutBorrowKind::ClosureCapture }) => {
                 first_borrow_desc = "first ";
                 self.cannot_reborrow_already_uniquely_borrowed(
                     span,
@@ -1085,10 +1103,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             (BorrowKind::Shared, BorrowKind::Shared | BorrowKind::Shallow)
             | (
                 BorrowKind::Shallow,
-                BorrowKind::Mut { .. }
-                | BorrowKind::Unique
-                | BorrowKind::Shared
-                | BorrowKind::Shallow,
+                BorrowKind::Mut { .. } | BorrowKind::Shared | BorrowKind::Shallow,
             ) => unreachable!(),
         };
 
@@ -1252,7 +1267,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         );
     }
 
-    fn suggest_split_at_mut_if_applicable(
+    fn suggest_slice_method_if_applicable(
         &self,
         err: &mut Diagnostic,
         place: Place<'tcx>,
@@ -1264,7 +1279,75 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             err.help(
                 "consider using `.split_at_mut(position)` or similar method to obtain \
                      two mutable non-overlapping sub-slices",
-            );
+            )
+            .help("consider using `.swap(index_1, index_2)` to swap elements at the specified indices");
+        }
+    }
+
+    /// Suggest using `while let` for call `next` on an iterator in a for loop.
+    ///
+    /// For example:
+    /// ```ignore (illustrative)
+    ///
+    /// for x in iter {
+    ///     ...
+    ///     iter.next()
+    /// }
+    /// ```
+    pub(crate) fn explain_iterator_advancement_in_for_loop_if_applicable(
+        &self,
+        err: &mut Diagnostic,
+        span: Span,
+        issued_spans: &UseSpans<'tcx>,
+    ) {
+        let issue_span = issued_spans.args_or_use();
+        let tcx = self.infcx.tcx;
+        let hir = tcx.hir();
+
+        let Some(body_id) = hir.get(self.mir_hir_id()).body_id() else { return };
+        let typeck_results = tcx.typeck(self.mir_def_id());
+
+        struct ExprFinder<'hir> {
+            issue_span: Span,
+            expr_span: Span,
+            body_expr: Option<&'hir hir::Expr<'hir>>,
+            loop_bind: Option<Symbol>,
+        }
+        impl<'hir> Visitor<'hir> for ExprFinder<'hir> {
+            fn visit_expr(&mut self, ex: &'hir hir::Expr<'hir>) {
+                if let hir::ExprKind::Loop(hir::Block{ stmts: [stmt, ..], ..}, _, hir::LoopSource::ForLoop, _) = ex.kind &&
+                    let hir::StmtKind::Expr(hir::Expr{ kind: hir::ExprKind::Match(call, [_, bind, ..], _), ..}) = stmt.kind &&
+                    let hir::ExprKind::Call(path, _args) = call.kind &&
+                    let hir::ExprKind::Path(hir::QPath::LangItem(LangItem::IteratorNext, _, _, )) = path.kind &&
+                    let hir::PatKind::Struct(path, [field, ..], _) = bind.pat.kind &&
+                    let hir::QPath::LangItem(LangItem::OptionSome, _, _) = path &&
+                    let PatField { pat: hir::Pat{ kind: hir::PatKind::Binding(_, _, ident, ..), .. }, ..} = field &&
+                    self.issue_span.source_equal(call.span) {
+                        self.loop_bind = Some(ident.name);
+                    }
+
+                if let hir::ExprKind::MethodCall(body_call, _recv, ..) = ex.kind &&
+                    body_call.ident.name == sym::next && ex.span.source_equal(self.expr_span) {
+                        self.body_expr = Some(ex);
+                }
+
+                hir::intravisit::walk_expr(self, ex);
+            }
+        }
+        let mut finder =
+            ExprFinder { expr_span: span, issue_span, loop_bind: None, body_expr: None };
+        finder.visit_expr(hir.body(body_id).value);
+
+        if let Some(loop_bind) = finder.loop_bind &&
+            let Some(body_expr) = finder.body_expr &&
+                let Some(def_id) = typeck_results.type_dependent_def_id(body_expr.hir_id) &&
+                let Some(trait_did) = tcx.trait_of_item(def_id) &&
+                tcx.is_diagnostic_item(sym::Iterator, trait_did) {
+                    err.note(format!(
+                        "a for loop advances the iterator for you, the result is stored in `{}`.",
+                        loop_bind
+                    ));
+                    err.help("if you want to call `next` on a iterator within the loop, consider using `while let`.");
         }
     }
 
@@ -1720,18 +1803,19 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             (
                 Some(name),
                 BorrowExplanation::UsedLater(LaterUseKind::ClosureCapture, var_or_use_span, _),
-            ) => self.report_escaping_closure_capture(
-                borrow_spans,
-                borrow_span,
-                &RegionName {
-                    name: self.synthesize_region_name(),
-                    source: RegionNameSource::Static,
-                },
-                ConstraintCategory::CallArgument(None),
-                var_or_use_span,
-                &format!("`{}`", name),
-                "block",
-            ),
+            ) if borrow_spans.for_generator() || borrow_spans.for_closure() => self
+                .report_escaping_closure_capture(
+                    borrow_spans,
+                    borrow_span,
+                    &RegionName {
+                        name: self.synthesize_region_name(),
+                        source: RegionNameSource::Static,
+                    },
+                    ConstraintCategory::CallArgument(None),
+                    var_or_use_span,
+                    &format!("`{}`", name),
+                    "block",
+                ),
             (
                 Some(name),
                 BorrowExplanation::MustBeValidFor {
@@ -1744,7 +1828,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     span,
                     ..
                 },
-            ) if borrow_spans.for_generator() | borrow_spans.for_closure() => self
+            ) if borrow_spans.for_generator() || borrow_spans.for_closure() => self
                 .report_escaping_closure_capture(
                     borrow_spans,
                     borrow_span,
@@ -2579,7 +2663,10 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     fn explain_deref_coercion(&mut self, loan: &BorrowData<'tcx>, err: &mut Diagnostic) {
         let tcx = self.infcx.tcx;
         if let (
-            Some(Terminator { kind: TerminatorKind::Call { from_hir_call: false, .. }, .. }),
+            Some(Terminator {
+                kind: TerminatorKind::Call { call_source: CallSource::OverloadedOperator, .. },
+                ..
+            }),
             Some((method_did, method_substs)),
         ) = (
             &self.body[loan.reserve_location.block].terminator,
diff --git a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index 1d430a93a..225c38efb 100644
--- a/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -6,10 +6,10 @@ use rustc_hir::intravisit::Visitor;
 use rustc_index::IndexSlice;
 use rustc_infer::infer::NllRegionVariableOrigin;
 use rustc_middle::mir::{
-    Body, CastKind, ConstraintCategory, FakeReadCause, Local, LocalInfo, Location, Operand, Place,
-    Rvalue, Statement, StatementKind, TerminatorKind,
+    Body, CallSource, CastKind, ConstraintCategory, FakeReadCause, Local, LocalInfo, Location,
+    Operand, Place, Rvalue, Statement, StatementKind, TerminatorKind,
 };
-use rustc_middle::ty::adjustment::PointerCast;
+use rustc_middle::ty::adjustment::PointerCoercion;
 use rustc_middle::ty::{self, RegionVid, TyCtxt};
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{sym, DesugaringKind, Span};
@@ -494,7 +494,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 } else if self.was_captured_by_trait_object(borrow) {
                     LaterUseKind::TraitCapture
                 } else if location.statement_index == block.statements.len() {
-                    if let TerminatorKind::Call { func, from_hir_call: true, .. } =
+                    if let TerminatorKind::Call { func, call_source: CallSource::Normal, .. } =
                         &block.terminator().kind
                     {
                         // Just point to the function, to reduce the chance of overlapping spans.
@@ -584,7 +584,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                         },
                         // If we see an unsized cast, then if it is our data we should check
                         // whether it is being cast to a trait object.
-                        Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), operand, ty) => {
+                        Rvalue::Cast(
+                            CastKind::PointerCoercion(PointerCoercion::Unsize),
+                            operand,
+                            ty,
+                        ) => {
                             match operand {
                                 Operand::Copy(place) | Operand::Move(place) => {
                                     if let Some(from) = place.as_local() {
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 20370e4c6..d292611e6 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -13,8 +13,9 @@ use rustc_index::IndexSlice;
 use rustc_infer::infer::LateBoundRegionConversionTime;
 use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::{
-    AggregateKind, Constant, FakeReadCause, Local, LocalInfo, LocalKind, Location, Operand, Place,
-    PlaceRef, ProjectionElem, Rvalue, Statement, StatementKind, Terminator, TerminatorKind,
+    AggregateKind, CallSource, Constant, FakeReadCause, Local, LocalInfo, LocalKind, Location,
+    Operand, Place, PlaceRef, ProjectionElem, Rvalue, Statement, StatementKind, Terminator,
+    TerminatorKind,
 };
 use rustc_middle::ty::print::Print;
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
@@ -414,7 +415,12 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     if !is_terminator {
                         continue;
                     } else if let Some(Terminator {
-                        kind: TerminatorKind::Call { func, from_hir_call: false, .. },
+                        kind:
+                            TerminatorKind::Call {
+                                func,
+                                call_source: CallSource::OverloadedOperator,
+                                ..
+                            },
                         ..
                     }) = &bbd.terminator
                     {
@@ -622,8 +628,7 @@ impl UseSpans<'_> {
                 err.subdiagnostic(match kind {
                     Some(kd) => match kd {
                         rustc_middle::mir::BorrowKind::Shared
-                        | rustc_middle::mir::BorrowKind::Shallow
-                        | rustc_middle::mir::BorrowKind::Unique => {
+                        | rustc_middle::mir::BorrowKind::Shallow => {
                             CaptureVarKind::Immut { kind_span: capture_kind_span }
                         }
 
@@ -839,7 +844,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         debug!("move_spans: target_temp = {:?}", target_temp);
 
         if let Some(Terminator {
-            kind: TerminatorKind::Call { fn_span, from_hir_call, .. }, ..
+            kind: TerminatorKind::Call { fn_span, call_source, .. }, ..
         }) = &self.body[location.block].terminator
         {
             let Some((method_did, method_substs)) =
@@ -859,7 +864,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 method_did,
                 method_substs,
                 *fn_span,
-                *from_hir_call,
+                call_source.from_hir_call(),
                 Some(self.infcx.tcx.fn_arg_names(method_did)[0]),
             );
 
@@ -1045,7 +1050,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             Some(def_id) => type_known_to_meet_bound_modulo_regions(
                                 &self.infcx,
                                 self.param_env,
-                                tcx.mk_imm_ref(tcx.lifetimes.re_erased, ty),
+                                Ty::new_imm_ref(tcx, tcx.lifetimes.re_erased, ty),
                                 def_id,
                             ),
                             _ => false,
@@ -1141,6 +1146,12 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     // Avoid pointing to the same function in multiple different
                     // error messages.
                     if span != DUMMY_SP && self.fn_self_span_reported.insert(self_arg.span) {
+                        self.explain_iterator_advancement_in_for_loop_if_applicable(
+                            err,
+                            span,
+                            &move_spans,
+                        );
+
                         let func = tcx.def_path_str(method_did);
                         err.subdiagnostic(CaptureReasonNote::FuncTakeSelf {
                             func,
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index d0e17bf5a..1f2fefadf 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -123,13 +123,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     item_msg = access_place_desc;
                     debug_assert!(self.body.local_decls[ty::CAPTURE_STRUCT_LOCAL].ty.is_ref());
                     debug_assert!(is_closure_or_generator(
-                        Place::ty_from(
-                            the_place_err.local,
-                            the_place_err.projection,
-                            self.body,
-                            self.infcx.tcx
-                        )
-                        .ty
+                        the_place_err.ty(self.body, self.infcx.tcx).ty
                     ));
 
                     reason = if self.is_upvar_field_projection(access_place.as_ref()).is_some() {
@@ -234,7 +228,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     borrow_spans.var_subdiag(
                     None,
                     &mut err,
-                    Some(mir::BorrowKind::Mut { allow_two_phase_borrow: false }),
+                    Some(mir::BorrowKind::Mut { kind: mir::MutBorrowKind::Default }),
                     |_kind, var_span| {
                         let place = self.describe_any_place(access_place.as_ref());
                         crate::session_diagnostics::CaptureVarCause::MutableBorrowUsePlaceClosure {
@@ -300,7 +294,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                             _,
                             mir::Rvalue::Ref(
                                 _,
-                                mir::BorrowKind::Mut { allow_two_phase_borrow: false },
+                                mir::BorrowKind::Mut { kind: mir::MutBorrowKind::Default },
                                 _,
                             ),
                         )),
@@ -416,12 +410,28 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         _,
                     ) = pat.kind
                 {
-                    err.span_suggestion(
-                        upvar_ident.span,
-                        "consider changing this to be mutable",
-                        format!("mut {}", upvar_ident.name),
-                        Applicability::MachineApplicable,
-                    );
+                    if upvar_ident.name == kw::SelfLower {
+                        for (_, node) in self.infcx.tcx.hir().parent_iter(upvar_hir_id) {
+                            if let Some(fn_decl) = node.fn_decl() {
+                                if !matches!(fn_decl.implicit_self, hir::ImplicitSelfKind::ImmRef | hir::ImplicitSelfKind::MutRef) {
+                                    err.span_suggestion(
+                                        upvar_ident.span,
+                                        "consider changing this to be mutable",
+                                        format!("mut {}", upvar_ident.name),
+                                        Applicability::MachineApplicable,
+                                    );
+                                    break;
+                                }
+                            }
+                        }
+                    } else {
+                        err.span_suggestion(
+                            upvar_ident.span,
+                            "consider changing this to be mutable",
+                            format!("mut {}", upvar_ident.name),
+                            Applicability::MachineApplicable,
+                        );
+                    }
                 }
 
                 let tcx = self.infcx.tcx;
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index 8ec872e20..617c85174 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -508,7 +508,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         let generic_arg = substs[param_index as usize];
                         let identity_substs =
                             InternalSubsts::identity_for_item(self.infcx.tcx, adt.did());
-                        let base_ty = self.infcx.tcx.mk_adt(*adt, identity_substs);
+                        let base_ty = Ty::new_adt(self.infcx.tcx, *adt, identity_substs);
                         let base_generic_arg = identity_substs[param_index as usize];
                         let adt_desc = adt.descr();
 
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
index f38e1605f..074f37bed 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -928,7 +928,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
 
     fn any_param_predicate_mentions(
         &self,
-        predicates: &[ty::Predicate<'tcx>],
+        clauses: &[ty::Clause<'tcx>],
         ty: Ty<'tcx>,
         region: ty::EarlyBoundRegion,
     ) -> bool {
@@ -937,10 +937,10 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             if let ty::GenericArgKind::Type(ty) = arg.unpack()
                 && let ty::Param(_) = ty.kind()
             {
-                predicates.iter().any(|pred| {
+                clauses.iter().any(|pred| {
                     match pred.kind().skip_binder() {
-                        ty::PredicateKind::Clause(ty::Clause::Trait(data)) if data.self_ty() == ty => {}
-                        ty::PredicateKind::Clause(ty::Clause::Projection(data)) if data.projection_ty.self_ty() == ty => {}
+                        ty::ClauseKind::Trait(data) if data.self_ty() == ty => {}
+                        ty::ClauseKind::Projection(data) if data.projection_ty.self_ty() == ty => {}
                         _ => return false,
                     }
                     tcx.any_free_region_meets(pred, |r| {